yo BYZANTINE CHURCHES CHAP. gallery, and after attending to his private devotions there3 took his place in the parakypticon («/ re3 TrapaKVTrTi/ctj) rov 0v<ruiarTi)piov), at the north-eastern or south-eastern end of the gallery3 whence he could overlook the bema and follow the public service at the altar.1 In due course the Communion elements were brought and administered to him in the chapel of the Theotokos ; he then retired to the meta-torion (a portion of the gallery screened off with curtains)5 while the members of his suite also partook of the Communion in that chapel. At the close of the service he and his guests partook of some light refreshments., biscuits and wine, in a part of the gallery fitted up for that purpose,, and thereafter returned to the palace. ^Architectural Features In the description of the architectural features of the church and for the plans and most of the illustrations in this chapter I am under deep obligation to Mr. A. E. Henderson, F.S.A. The information gained from him in my frequent visits to the church in his company3 and from his masterly article on the church which appeared in the Builder of January 19065 has been invaluable. In design the church is an octagonal building roofed with a dome and enclosed by a rectangle, with a narthex along the west side. This was a favourite type of ecclesiastical architecture, and is seen also in another church of the same period, San Vitale of Ravenna, in which Justinian and Theodora were interested. There, however, the octagonal interior is placed within an octagonal enclosure. The adoption of a rectangular exterior in the Constantinopolitan sanctuary is a characteristic Byzantine feature.2 S. Vitale was founded in 526, a year before SS. Sergius and Bacchus. As an examination of the plan will show, the architect's 1 Similar to the parakypticon at the east end of the southern gallery in S. Sophia. Reiske (Comment, ad Constant. Porphyr, p. 195) defines it as * Fenestra, quae in sacrificatorium despicit e catechumeniis/ CF. on the whole subject, Antoniadi, "B^/Mwrw T^J 'A*yŁa* So^fosr, vol. ii. p. 29i,npte xoi 5 p. 331, note 190 ; p. 332. 2 The plan of SS. Sergius and Bacchus is similar to that of the cathedral of Bosra (51 i-xat), which was also dedicated to the same saints. Fergussori, History of Ancient and Mediaeval Architecture., vol. i. p. 432.